In 2014, the V8 team deprecated v8::Handle in favor of v8::Local for local handles. Electron 5.0 includes a version of V8 that has finally removed v8::Handle for good, and native Node.js addons that still use it will need to be updated before they can be used with Electron 5.0.

The required code change is minimal, but every native Node module that still uses v8::Handle will fail to build with Electron 5.0 and will need to be modified. The good news is that Node.js v12 will also include this V8 change, so any modules that use v8::Handle will need to be updated anyway to work with the upcoming version of Node.

If you maintain a native addon for Node.js, ensure you replace all occurrences of v8::Handle with v8::Local. The former was just an alias of the latter, so no other changes need to be made to address this specific issue.

You may also be interested in looking into N-API, which is maintained separately from V8 as a part of Node.js itself, and aims to insulate native addons from changes in the underlying JavaScript engine. You can find more information in the N-API documentation on the Node.js website.

If you're consuming a native addon for Node.js in your app and the native addon will not build because of this issue, check with the author of the addon to see if they've released a new version that fixes the problem. If not, reaching out to the author (or opening a Pull Request!) is probably your best bet.